The Mitsubishi G4M bomber (Allied code name: “Betty”) was the premier twin engine bomber of the Japanese Navy in World War II. It was designed for long range; it could carry a ton of bombs or torpedoes over 3000 miles. To get this range, the Betty, like most Japanese planes of the period, had no armor or protection. Its large fuel capacity and lack of protection for the gas tanks made it extremely flammable; Allied pilots called it the “One-shot Lighter” and the “Flying Cigar”. The G4M was introduced in May 1941 and over 2400 copies were produced during the war. Two 1500-hp air-cooled engines gave it a maximum speed of 270 mph, while defensive armament included 3 machine guns and a 20 mm gun in the tail.
The Betty made its combat debut in China, but the war in the Pacific made it famous. Torpedo-carrying Betties took part in the sinking of the HMS Prince of Wales and HMS Repulse during the Malaya campaign, the first time in history that heavy ships were sunk at sea purely by air attack. However, when Rabaul-based G4Ms attempted to repeat this feat against the aircraft carrier USS Lexington in February 1942, 16 (out of 18) of the bombers were shot down, and not a single hit was scored. (See: "Butch" O'Hare). The G4M was active in every theater of the Pacific War, and was in service up to the surrender. Probably the most famous incident involving the plane was the assassination of Admiral Isoroku Yamamoto, who was flying in a Betty when he was ambushed by American fighters and shot down. Later Betties were modified to carry the Ohka human piloted missile for kamikaze attacks. Specially marked G4Ms even played a part in the very last chapter of the war, when they were used to ferry Japanese delegates to the surrender ceremonies.
See also: the Battle of Rennell Island
- The Illustrated Encyclopedia of Combat Aircraft of World War II, by Bill Gunston, Salamander Military Press, 1990
- Zero, by Masatake Okumiya, Jiro Horikoshi, and Martin Caidin, 2004
- Mitsubishi Type I Rikko Betty Units of World War 2, by Osamu Tagaya, Osprey Publishing, 2001